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David Mech, National Biological Survey

/ S t first glance, arctic Alaska may appear to be a barren wasteland.

' " Yet, in reality, this cold desert teems with life. Myriad plants and

animals are native to this treeless plain above the Arctic Circle. In
summer, the upper part of the ground (about 10 centimeters) thaws for just a
short period, triggering frantic activity for the region’s denizens.

This area is resource “rich” in many ways. One of the world’s largest oil
fields, for example, is located at Prudhoe Bay, Alaska. Oil from that site
travels southward more than 1,200 kilometers to Valdez, Alaska, through
the Trans- Alaska Pipeline. Oil from Prudhoe Bay accounts for about a
quarter of total U.S. oil production.

In this article and on the accompanying foldout, we explore the unique
features of Alaska’s arctic ecosystem, with a focus on the special adaptations
of plants and animals that enable them to survive in a stressful climate. We
also review the challenges facing public and private land managers who seek
to conserve this ecosystem while accommodating growing demands for
development. With the classroom activities we’ve included, you can help
students understand why fragile arctic soils are slow to recover once dis¬
turbed; why arctic animals look so different from their desert counterparts;
and how to evaluate the pros and cons of oil development along the arctic
coast, an issue that will likely be debated into the 21st century.

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By Jeff Brune, Robert King, Mike Kunz, Richard Brook, and Mary Tisdale

Reprinted with permission from Science
and Children. Copyright © 1996 by NSTA.

SCIENCE AND CHILDREN 29

MAY 1996

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ARCTIC NATIONAL
WILDLIFE REFUGE

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PRESERVE

^/ftctic Alaska, the area of the state
north of the Arctic Circle, has
three distinct regions: the arctic coastal
plain, the Brooks Range, and
the boreal forest with its
numerous lakes, rivers, and
streams.

The arctic coastal plain, or
the “North Slope,” includes 14
percent of Alaska’s land.

Blanketed by tundra and dotted
with lakes and ponds, it
receives less than 16 centime¬
ters of moisture annually (less
than the Mojave Desert).

Despite meager precipitation,
most of the coastal plain is
classified as wetlands. The
underlying permafrost (perma¬
nently frozen ground) inhibits
drainage, and the small amount
of melt water or rain that soaks
into the tundra remains near the
surface. Most inhabitants of the
North Slope live in one of eight
communities, seven of which
are along the coast. The largest
communities are Barrow and
Kotzebue. Barrow, at about
1 ,300 kilometers from the North Pole,

is the northernmost
inhabited village in
North America.

South of the North
Slope lie the rugged
peaks of the Brooks
Range, which runs across
northern Alaska for
1,150 kilometers. The
range rises over one kilo¬
meter at its western end,
and nearly three kilome¬
ters in its eastern peaks.
Although white spruce
and other trees appear in
some sheltered valleys,
the slopes are generally
bare except for a thin
layer of hardy tundra
vegetation, such as lichen. From the
highest peaks, rivers flow south to the
Yukon River, north to the Beaufort
Sea, or west to the Chukchi Sea.

The south slope of the Brooks
Range, sheltered from ocean winds,

A whale harvest in Barrow, one of the eight
communities of the North Slope.

The rugged peaks of arctic Alaska’s Brooks Range
rise from one to three kilometers.

-J

grows more varied tundra vegetation
and forests of small trees. The
Russians called this region “taiga,” a
land of scattered dwarfed conifers, and
for good reason: Trees grow so slowly
in the taiga that scientists have mea¬
sured century-old spruces with trunks
no more than 30 centimeters in diame¬
ter. The average white spruce in the
taiga is only six meters high, even after
a century of growth.

/n order for arctic animals to survive
in their arid, windy, and frigid envi¬
ronment, nature has equipped these
creatures to find food and shelter and to
produce offspring. The accompanying
foldout highlights many of the unique
adaptations of arctic plants and animals
and provides activities that can help stu¬
dents understand how adaptations work.

Arctic Alaska’s human inhabitants
have also adapted to cope with the
environment. With temperatures aver¬
aging well below freezing during most
months, the need to stay warm is para¬
mount. Semi-subterranean “pit” houses
were used from prehistoric times until
recently. These homes, built of sod and
other natural insulation, were very effi¬
cient at holding in the heat. Modern
arctic houses now resemble those in
the lower 48 states, yet contain more
insulation and are often built on pilings
to allow cold air to circulate under the
house. This ensures that the warmth of
the house won’t melt the underlying
permafrost and cause the structure to
sink.

CfoSfMjres

jr Iver two-thirds of arctic Alaska is
ly federally owned land, managed by
the Bureau of Land Management, the
U.S. Fish and Wildlife Service, and the

30 SCIENCE AND CHILDREN

MAY 1996

WWl

Brilliantly colored flowers bloom in the arctic
summer.

National Park Service. Americans
depend on these agencies to properly
manage Alaska’s tundra regions to
meet a variety of human and environ¬
mental needs. In meeting their respon¬
sibilities, these agencies are grappling
with a number of tough environmental
challenges and issues.

The Fragile Tundra. The soils of
the Arctic are very susceptible to dam¬
age if disturbed by animals or humans.
Some biologists estimate, for example,
that it may take up to 40 years for
lichens to recuperate from the munch¬
ing and treading of a passing herd of
caribou (some lichen growth has been
measured at a sixth of a centimeter per
year).

The land of the North Slope is
underlain with permafrost, insulated on
top by shallow-rooted, low-lying vege¬
tation. In the summer, the sun’s radiant
energy thaws the frozen surface down
about 1 0 centimeters, with the melted
snow water unable to seep into the
frozen ground below. Consequently,
the region is largely wet and boggy,
with over a million shallow lakes.
Crossing the terrain by foot in the sum¬
mer is difficult, because the surface
consists of areas of elevated grassy tus¬
socks alternating every 10 centimeters

with small, sunken pools of stagnant
standing water.

As long as the permafrost is insulat¬
ed from heat by the surface vegetation,
it can remain stable for many thou¬
sands of years. On the other hand, even
small disturbances to the vegetation
rootmat can start a process of destabi¬
lization that can reach impressive
proportions.

Experience has taught us about the
fragile nature of this land. In the
post-World War II period, exploration
for oil and gas involved the use of
mechanized vehicles that damaged the
insulating vegetation. When the vege¬
tation was damaged, the permafrost
was no longer insulated from the sum¬
mer sun, causing the frozen soil to
melt. Eventually, this resulted in mas¬
sive artificial bogs and
swampy areas. In some
places, these scars,
though decades old, are
still evident.

Crossing the tundra
without damaging the
permafrost is an ongoing
challenge. Much of
today’s permafrost
degradation is triggered
by road-building and
other construction activi¬
ties that strip away or
disturb the vegetation.

Over the years engineers have learned
to work in winter and to avoid disturb¬
ing the vegetation. For example, in
building the Dalton Highway, an all-
weather road that extends north 650
kilometers from interior Alaska to the
Prudhoe Bay oil fields, engineers
placed the roadbed on top of the vege¬
tation rather than cutting into the sur¬
face as is the common practice in road¬
building. In some areas, sheets of plas¬
tic-foam insulation were placed on the
vegetation to provide additional ther¬
mal protection before the roadbed
material was laid down. Moreover,
mechanized vehicles may use the road
only in periods of adequate snow cover

(15 or more centimeters) in order to
blunt the impact on the tundra. In other
cases, temporary ice roads are built.
Even air-cushioned vehicles have been
tried as a way to avoid damaging the
tundra.

Unfortunately, despite innovations
in road and building construction, the
fragility of the tundra remains a para¬
mount issue in the Arctic today. Other
concerns in the region include ozone
depletion, solid waste disposal, and
pollution of the Arctic Ocean.

Ozone Depletion. The effect of
ozone depletion is of particular impor¬
tance to life in the Arctic and
Antarctic, as the phenomenon is most
severe over polar regions. In the win¬
ters, “ozone holes” develop over the
poles. Research points to certain

A summertime view of the North Slope’s Kanuti
Flats shows why the region is considered a
wetland.

human-made chemicals, chlorofluoro-
carbons, being major contributors to
this situation. Researchers in the Arctic
are investigating how plants that sup¬
port the food chain may be impacted
by ozone depletion.

Solid Waste Disposal. Disposing of
solid waste is another major problem in
the Arctic because permafrost limits the
construction of sanitary landfills, and
low temperatures inhibit bacterial
decomposition of organic wastes.
Scientists have detected the effects of
human wastes from Inupiat (native

MAY 1996

SCIENCE AND CHILDREN 31

BLM

Alaskan) settlements centuries after the
inhabitants have gone. Today, organic
waste is collected and hauled to sewage
dumping areas or burned in oil barrels.

Pollution of the Arctic Ocean.
Recent reports of nuclear waste conta¬
mination and massive oil spillages from
broken pipelines in Siberia have once
again raised concerns about pollution
of the Arctic Ocean. The oil spillages
have been near river systems that drain
into the Arctic Ocean. Because the
Arctic Ocean is a major source of fish,
whales, seals, and walrus (of cultural
and economic importance to local

Musk oxen stand in a defensive posture. These

animals were extenninated from the North Slope
in the late 1800s by sport-hunters, but 64 musk
oxen reintroduced into the coastal plain in 1969
and 1970 have now multiplied to a thriving popu¬
lation of 550.

Inupiat), the consequences of polluting
it would severely affect the human pop¬
ulation as well as the environment in
general.

Global Warming. About 14,000
years ago, arctic Alaska’s climate
began to change. Although the reasons
for the change are not completely
understood, the major factors of solar
radiation, the winds of the jet stream,
and ocean current fluctuation were
involved. This climate change resulted
in a major alteration in nature and
caused the extinction of most of the Ice
Age herbivores as well as the carni¬
vores that preyed on them. A few large
predators, such as the grizzly bear and
wolf, survived, as did a few of the less
common Ice Age herbivores that were

32 SCIENCE AND CHILDREN

better suited to the new ecosystem than
the old one, such as moose, musk
oxen, and caribou. It was a difficult
time for the human population also,
because of the declining food resources
and the fluctuating climate.

Some scientists predict that the
results of global warming over the next
century will be very similar to the effect
of past warming events on the perma¬
frost and on the arctic ecosystem. Of
special concern is the peat that lies
beneath the tussock-tundra covering
most of arctic Alaska, Canada, and
Russia. These arctic peat deposits con¬
tain huge amounts of C02; if the climate
warms enough that the peat thaws and
begins to decompose, all of that C02
would be released into the atmosphere.
The increase in atmospheric C02
could cause an increase in surface tem¬
peratures, which in turn could cause the
rate of peat decomposition to accelerate,
generating more C02. The onset of an
ever-increasing C02 production cycle in
the Arctic could have a significant effect
on ecosystems worldwide.

Ironically, a climatic alteration that
brought the first humans to North
America thousands of years ago may
provide insight into a contemporary
climatic change that could affect mod¬
ern humans and alter the course of civ¬
ilization once again.

/j re-tie- Wtetiereti

y? he 7.7 million-hectare Arctic
/ National Wildlife Refuge,
commonly referred to as “ANWR”
(pronounced “an war”), is the nation’s
largest wildlife refuge. ANWR supports
169 species of birds, 38 species of fish,
44 species of mammals, an unknown
number of species of flowering plants,
and more than 2,000 species of lichens
and bryophytes (mosses and liverworts).

In recent years, Congressional
debates about allowing oil and gas

development in ANWR have brought
attention to this issue. The question is,
What are the impacts of oil and gas
development, including pipeline con¬
struction, on wildlife and on the Inupiat
and other northern peoples who subsist,
in part, on this wildlife? Opinions vary
on the answer, with some people pre¬
dicting little effect, while others foresee
drastic impacts brought about by sub¬
stantial changes to the migration and
calving patterns of caribou.

At stake for consumers is the nation’s
most promising onshore petroleum
prospect. Geologists have determined
that there is a 19 percent chance of find¬
ing recoverable oil deposits within
ANWR’s coastal plain. No one knows
how large the potential oil reservoir is,
but federal land managers estimate there
may be enough oil in that field to supply
at least 10 percent of the nation’s fuel
for the next 20 years.

At stake for conservationists is the
biologically productive arctic coastal
plain. Often referred to as “America’s

Inupiat children from the village of Wainwright on
the arctic Alaskan coast brave a howling winter
storm.

Fred Hirschmann

The Trans-Alaska Pipeline near the Richardson
Highway. This line carries oil from Prudhoe
Bay to Valdez.

Serengeti,” the coastal plain

■ serves as an important calving
ground for the Porcupine caribou herd;

■ contains about 75 percent of the
year-round musk ox range;

■ provides an important gathering area
for more than 100,000 lesser snow
geese;

■ is frequently used for maternity dens
by polar bears in winter;

■ and is used by birds from six conti¬
nents, who flock there to raise their
young.

Research may help answer some of
the issues surrounding ANWR, but pol¬
itics and the worldwide price of oil will
no doubt strongly influence the
progress of development in this part of
the world.

%Mfmtio/mt$

y^rimarily as a result of the ongoing
debate about the future of
ANWR, an increasing number of
wilderness adventurers have been visit¬
ing the refuge to see for themselves
what the debate is about. The number
of outfitters offering backpacking and
river trips increased from one in 1975
to 15 in 1995. One result has been that
the amount of river usage during the
short summer has increased dramati¬
cally. A “visitor-use day” indicates one

person using an area for all or part of a
day; in 1984 ANWR had 702 visitor-
use days, and in 1995 it had 3,182 visi¬
tor-use days. As a result, congestion on
the rivers and air traffic in and out of
the refuge have grown. As recreation
use intensifies, so will impacts on the
ecosystem, and decisions will have to
be made on whether to limit access to
ANWR.

£ooh>tf? to t/w piotttro'

laska’s tundra seems immense,
remote, and largely untouched by
humans. Yet, as the human population
in this region increases and as resource

development grows, human actions
will have a long-lasting and cumulative
impact in the ecosystem. Meeting the
needs of people today while protecting
our resources for the future will be a
big challenge.

As tomorrow’s decision-makers,
today’s students will play a big role in
determining how well we meet that
challenge. Complex legal, political,
ecological, economic, and social rami¬
fications will have to be considered.
Few issues will have simple solutions,
and resolving them will undoubtedly
involve compromise. By introducing
children to these ideas now, educators
can help prepare them for the future.

. . . . . .

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archaeological evidence suggests that it wasn’t until 14,000 to
13,000 years ago that humans migrated into North America by
crossing from Siberia to Alaska via the Bering land bridge.

Most researchers agree that to survive in arctic and subarctic environ¬
ments, ancient humans had to be able to make clothing that was generally
form-fitting and relatively weather-tight. Such clothing was probably made
by fastening pieces of animal hide together with sinew. The invention of the
awl, a pointed implement used for stitching together animal skins for gar¬
ments and other uses, was the technological breakthrough that most likely
enabled ancient peoples to begin to colonize cold regions. The eyed needle,
which evolved from the awl and is found on 30,000-year-old Russian camp¬
sites, would have allowed strong, weather-tight, and, in some cases, water¬
tight clothing seams to be made.

The importance of this small aspect of prehistoric technology — a simple
needle — and its effect in terms of human occupation of the Western
Hemisphere is almost unbelievable. Humans who settled in North and
South America got there by migrating through the Arctic. Without the
needle, they could not have done it.

Although it took roughly 15,000 years from the time that needles
first appeared until humans were living in the Arctic, it can easily be
said that this simple tool and those skilled in its use were responsible,
in part, for the human occupation of the New World.

'£

MAY 1996

SCIENCE AND CHILDREN 33

FOE TUE CMSSFOOM

lant growth is essential in the tundra envi¬
ronment, as plants are the primary food
source for the rest of the consumers in the
food chain. Plant growth and decomposition are
constrained by the comparatively small amount of
light and heat and by the very short but intense
growing season. These limiting factors affect the
ability of wildlife and plants to reproduce success¬
fully and to maintain their populations over time.

The following activities demonstrate the effects
of temperature and freezing on decomposition and
the effect of permafrost on plant growth.

Procedure: Have students put an apple slice in
each of the sealed containers, and place each contain
er in a different environment: a cold place, a cool
place, a warm place, and a hot place. Keep the light
conditions reasonably similar in each environment.
Then let a child lay the thermometer alongside each
apple slice, and measure and record the temperature
in each place. Have students examine the containers
once each week and record the changes. What did
they observe? How did cold affect the process of
decay? (Cooler temperatures keep the microorgan¬
isms that decompose matter from multiplying quick¬
ly, which slows the rate of decomposition.)

The honeycomb of polygonal shapes is the result of the seasonal
churning of the ground above the underlying layer of permafrost.

/ decomposers are a crucial link in food chains
and food webs because they return to the soil
organic compounds that enhance plant growth.
Decomposition is slower in the far North than in
the rest of North America. Because decomposing
matter takes longer to become integrated into the
soil, plant growth may be limited by the lack of
organic compounds in the soil. The slow process of
soil formation in cool climates means that existing
soil is slow to recover from disturbance by humans,
animals, or the forces of erosion.

Have students try the following activity to help
them understand the effect of cool temperatures on
decomposition. Prior to the investigation, record
students’ hypotheses about how temperature relates
to decomposition.

Materials: You will need four fresh apple slices,
four sealable plastic containers, and a thermometer.

^^lthough decomposition is limited by the arctic
1^7 climate, freezing and thawing actually speed
access for bacteria and fungi to the insides of the
cells of dead plants and animals. This is because
water in tissue cells expands when it freezes, thus
breaking cell walls and opening the inner cells to
invasion once the tissue thaws. Nevertheless, the
net effect of the arctic climate is to slow the rate of
decomposition.

Materials: You will need four potatoes about
the same size, two shallow dishes, a set of scales,
and access to a freezer.

Procedure: Ask students to predict which potato
will decay first: one that has been frozen and then
thawed, or one that has never been frozen. Students
should record their predictions and reasoning in their
journals. Then have the children measure the mass
of two potatoes and freeze them. The next day, thaw
the potatoes in the open air and again measure their
mass. Measure the mass of two potatoes that have
not been frozen. How do they all compare? Have
students squeeze a once-frozen and a never-frozen
potato. Does water come out of both? Where did the
water come from? (A living cell contains 85-90 per¬
cent water. When water inside the cell freezes and
expands, the cell walls break. Thus the once-frozen
potato releases more water than the never-frozen
potato.) Next, have the class place in two labeled
dishes the once-frozen potato and the never-frozen
potato that were not squeezed. Keep both containers
in the same location. Students should then observe
and keep a daily record of changes in the potatoes
for two weeks. (The once-frozen potato should
decompose at a faster rate because when the water in
its tissue cells froze and expanded, breaking the cell

34 SCIENCE AND CHILDREN

MAY 1996

FOX TFE CM 55X00X1

Large blocks of tundra-covered sediment, bounded by ice-wedge
polygons, collapse into the Beaufort Sea as a result of mechanical
and thermal erosion of the ice-rich sediment by wave action.

walls, the inner cells were opened to invasion once
the tissue thawed.)

yQermafrost, or permanently frozen ground,
underlies all lowland tundra areas (except
large lakes and rivers) in the Arctic. When present,
permafrost and seasonal frost play an important
part in shaping tundra lands and ecosystems.
Permafrost prevents plant roots from penetrating
deeply into the soil and leads to unstable growth —
without a strong anchorage, even large plants could
be ripped out of the ground by the wind.

Permafrost also retards the percolation and infil¬
tration of ground water into the soil, and in some
low-lying areas, can lead to shallow, water-covered
formations known as peat bogs. Water-saturated
soils and peat bogs restrict the variety of support¬
able life-forms in the tundra. The following investi¬
gation gives students an opportunity to observe the
effects of permafrost on soil.

Materials: You will need two shallow baking
pans, a sealable plastic container, soil, tap water, a
fork, a tablespoon, and access to a freezer.

Procedure: Day 1 — Have students completely
fill a plastic container with tap water and seal it
securely with a lid. Ask students to predict what
will happen after the water-filled container has
been in the freezer for several hours. Then, have
the children put moist soil to a depth of about 5 cm
into each of the two pans. Ask students what they
think will happen when a soil-filled pan has been
in the freezer for several hours. Place both the
water-filled container and one of the soil-filled

pans in a freezer overnight. Put the other soil-filled
pan aside.

Day 2 — Explain to students that permafrost is a
word used to describe soil that is frozen year-
round. Ask the class how they think permafrost
might differ from unfrozen soil. Ask them to think
about the following questions:

■ Would permafrost be warmer or colder than
regular soil?

■ Would it be harder or softer?

■ Would it soak up more or less water?

■ Would it take up more or less space?

Next, retrieve the pan of soil from the freezer
and have students test their predictions by compar¬
ing the frozen soil with the unfrozen soil set aside
the previous day. Ask a student to find out which
soil is harder by using a fork. Next, have students
pour a spoonful of water first on the frozen soil and
then on the unfrozen soil. What happens to the
water? Does one type of soil soak it up more readi¬
ly? Remove the water-filled container from the
freezer. Ask students what made the container’s
sides push out or break. Explain that water expands
when it freezes. There was not enough space in the
plastic container to hold the water once it had
frozen and expanded. Using the information gath¬
ered from this lesson, ask the children to answer

Few people would identify this verdant vista as a part of arctic
Alaska.

the following question: “Why does a road break,
buckle, and form potholes in the spring?” (When
water seeps into cracks in rocks and then freezes
with falling temperatures, it expands and forces the
rock to break into smaller parts. Thus, ice wedging
occurs. Rocks are no different from city streets in
this regard.)

These activities were adapted with permission from Alaska’s Tundra
and Wildlife: Alaska Wildlife Curriculum Teacher’s Guide, published in
1995 by the Alaska Department of Fish and Game.

MAY 1996

SCIENCE AND CHILDREN 35

BLM

FOX FFE CMSSXOOffl

“perilling for oil in ANWR would help the United
far States become less dependent on oil from other
countries. Oil companies say they have developed
special building techniques, used in other arctic
regions, to reduce the effects of construction on the
environment and avoid harming the region’s
wildlife. However, many people think that drilling
for oil will damage the arctic ecosystem beyond
repair, pointing out that in other arctic regions
where oil wells have been drilled, toxic wastes
have been released into the environment. Shipping
the oil also can cause environmental problems,
as was painfully evident after the 1989 Exxon
Valdez spill.

In a wolf pack, only one pair has young but the entire pack works
to feed and protect the pups.

After researching this issue, have students
consider the pros and cons of drilling for oil along
the arctic coast of ANWR. With such an activity,
you might ask them to assume the role of a
member of Congress and to argue either in favor
of or against drilling in the refuge, or you might
have each student write a speech presenting his
or her reasoning.

/jfauf tfw/IttFfMrs

Jeff Brune is the environmental education coordinator for the
Bureau of Land Management (BLM) in Alaska. Archaeologists
Robert King, Mike Kunz, and Richard Brook are actively
involved with the BLM’s cultural resources programs. Mary
Tisdale is the national coordinator for the BLM’s environmental
education and volunteer programs.

Special thanks to David Mech, National Biological Survey; Phil
Garrett, Deputy Refuge Manager, Arctic National Wildlife
Refuge, Fish and Wildlife Service; Susan Holly, Gates of the
Arctic National Park and Preserve, National Park Service;
Harvey Hefferman, Arctic National Wildlife Refuge, Fish and
Wildlife Service; Frankie Barker, Executive Director, Alaska
Natural History Association; Colleen Matt, Program Director of
the Alaska Department of Fisheries and Game; Grant Spearman
of the Simon Paneak Museum; and to the following employees
of the Department of the Interior: Jeremy Brodie, Connie
Adkins, Jeff Denton, Shelly Fischman, Mike Scott, Bruce Seppi,
Jim Sisk, Van Waggoner, and the staff of the Department of the
Interior library.

Alaska Department of Fish and Game. (1995). Alaska’s tundra
and wildlife: Alaska wildlife curriculum teacher’s guide.
Juneau, AK: Author.

Kauffmann, J. (1992). Alaska’s Brooks Range. Seattle: The
Mountaineers.

Miller, D.S., Kaye, R., and Campbell, L.J. (1993). Arctic
National Wildlife Refuge. Alaska Geographic, 20(3).

Staff. (1989). North slope now. Alaska Geographic, 16(2).
Woerner, R.K. (1986). The Alaska handbook. Jefferson, NC:
McFarland.

Wuerthner, G. (1988). Alaska’s mountain ranges. Helena, MT:
American Geographic.

The following booklets, developed by the Alaska Department of
Fish and Game, are available for purchase: Alaska’s Tundra
and Wildlife ($13.95); Alaska’s Forests and Wildlife ($13.95);
Wildlife for the Future ($13.95); and Alaska’s Ecology
($12.95). Each contains relevant background information, les¬
son plans, activity sheets, and interdisciplinary hands-on activi¬
ties. Another booklet, Alaska Ecology Cards ($6.99), is required
for some of the activities and contains 270 illustrated cards with
biological information about arctic animals and plants. These
materials can be ordered from Circumpolar Press, Box 221944,
Anchorage, AK 99522; tel. 907-248-9921.

36 SCIENCE AND CHILDREN

MAY IS

n ,wto mit.z

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/V‘ 3-

lie front of this foldout depicts the Alaskan tundra in late spring. As the snow melts, the
f region 's flora and fauna become more visible and active. Purple monkshood, bog rose-
f mary (red), and tundra rose (yellow) grow and flower, as do many varieties of moss and

lichen (lower right). Often, plants in the nutrient-poor soil benefit from the spot fertilization of ani¬
mal droppings or the decayed remains of dead animals and plants. Tussocks of sedges and grass¬
es, which tend to grow in clumps (center right), provide food and shelter for wildlife but create a
tricky suiface for people to traverse on foot.

Along the stream, wedges of ice cut into the permafrost below. These wedges form in cracks
and grow slowly, helping to create the polygons of the patterned ground illustrated in the distance.
Also visible at the top of the stream cut, and partially insulating the exposed permafrost, is a flap
of vegetation and soil. It began to drape down toward the streambed after the soil supporting it
was eroded by the stream. Ice also is responsible for another prominent feature of the tundra, the

pingo (the hill on the far edge of the polygonal ground with red soils exposed). Essentially an ice-
filled blister, a pingo can attain a height of more than JO meters. Eventually the summit can rup¬
ture and thaw, creating a water-filled crater take or collapsing the structure altogether.

With warmer weather, patterns of animal life begin anew as caribou migrate, arctic foxes stalk
ptarmigans, musk oxen gather in defensive circles to ward off hungry wolves, and lemmings
emerge from the snow burrows that are their winter homes. On a smaller but no less significant
scale, swarms of insects take to the air, preying on animals and people alike.

The tundra 's human population is sparse. Permanent settlements are few and far between,
most being limit villages along the coast. Seasonal populations include scientists and naturalists.
Transportation is difficult and often accomplished by light aircraft and helicopters. But, as indicat¬
ed by the ancient arrowhead pictured, our ancestors traveled the area on foot, as long as 10-12
thousand years ago, hunting and making a life for themselves.

..SCIENCE

&CHHDREN

Jeff Brune is the environmental education coordinator for the
Bureau of Land Management (BLM) in Alaska. Shelly Fischman
is a program specialist and illustrator for the BLM.
Copyright 1996 by the National Science Teachers Association

/! CoM~Wwt/wr

By Jeff Brune

/rrkeep warm on a cold day, you might pile on extra clothing or have a
cup of hot chocolate. The nose bot fly of the frigid Arctic takes a decided¬
ly different approach to staying warm. It takes refuge in the warm, steamy
nose of a caribou. Once in the nostril, the fly withstands the snorts of the irri¬
tated animal and quickly deposits its wormy offspring. The maggots then
crawl through the caribou's nose passages and settle in its throat, where they
spend the winter warmed by the caribou’s
body heat and feed off its tissues. When spring
arrives, the well-fed maggots are coughed up
or sneezed to the ground, where they turn into
adult flies and begin the cycle again.

Keeping warm is no easy task on the arc¬
tic tundra, where winter lasts almost nine
months and temperatures can plunge to -55°C.
Even during the brief summer, when the land thaws
and the sun never sets, a sudden snowstorm can
freeze everything. Constant high winds rob the
environment of moisture and have a sandblast¬
ing effect, propelling sharp ice crystals and grit¬
ty dust that would tear a common houseplant to
shreds. When the growing season lasts only
10-14 weeks and the soil has few nutrients, it’s
not easy for plants to make food. Similarly,
when the sun sets for more than two months and
the only light to hunt by comes from the moon
or the eerie shimmer of the northern lights, ani¬
mals have a hard time finding sustenance.

Despite such difficult conditions, life manages
to survive in the Arctic because the plants and ani¬
mals that live there have special traits, or adaptations, that make them espe¬
cially suited for the cold, the persistent wind, and the brief growing season.
These unique adaptations can be physical traits (such as warm fur), behaviors
(such as hibernation), or physiological traits (such as the chemical processes
that allow certain arctic plants to make
food in low temperatures).

Snow goose. Attracted by
plentiful food, endless hours
of daylight in which to eat,
and a comparative lack of
predators, snow geese and
many other migrating birds
flock to the tundra during the
summer months.

Keeping Warm

Life-forms on the tundra have devised
numerous ways of dealing with the
arctic chill.

Many animals avoid the cold alto¬
gether. Millions of birds that flock to
the tundra during the summer months
fly south to warmer climates during the
winter. Vast herds of caribou also leave
the tundra in the winter and head for
the protective cover of northern forests,
although some caribou remain on the
tundra through the winter months.

The hardy residents that stay in the
Arctic year-round have developed spe¬
cial adaptations to brave the chill.

Musk oxen, for example, have two layers of protective fur. The outer layer
is made of long hairs that protect the animal from wind and water. The
woolly inner layer of fur traps air next to the body. Body heat warms the
air, keeping the musk ox cozy even at -40°C! Other furry arctic animals
include brown bears, caribou, wolves, ground squirrels, foxes, and hares.

Arctic tern. These birds create
their own "endless summer ”
by commuting between the
Arctic and Antarctic, visiting
each during periods of con¬
stant daylight.

Saxifrage. Like many arctic
plants, saxifrage grows low to
the ground, where it absorbs
heat radiated from the soil in
the summer and is protected
from winds and wind-borne
ice by a blanket of snow in
the winter.

Even birds have responded similarly to
the cold, developing thick layers of
feathers. The willow ptarmigan, for
example, has water-repellent outer
feathers in addition to inner feathers.
These birds, which live year-round in
the Arctic, even grow feathers on the
soles of their feet! These feathers keep
feet warm and double as snowshoes to
prevent the bird from sinking into the
snow.

When fur or feathers are not

enough to stay warm, arctic animals seek shelter. For example, to
escape the cold winter winds, the ptarmigan takes flight and
dives into a drift of soft snow. The snow blankets the
and acts as a good insulator, trapping heat that comes
the ground. Diving from the air. the ptarmigan leaves
tracks for predators to follow.

Plants shelter themselves from the arctic elements
growing low to the ground. In the arctic .summer, the dark
colored ground absorbs energy from the* sun, so plants
close to the warm ground rather than towering above it
In the winter, snow blankets and protects arctic
plants from the wind and cold. Any twigs that do
extend above the snow are slowly ground down by
the sharp ice and snow blowing along the surface.

Insects battle the cold in many intriguing ways.

All insects are cold-blooded and even on a summer
arctic day, the chill in the air can make it difficult for
them to move, let alone fly. So insects first need to
warm up. Billions of mosquitoes, midges, gnats, crane
flies, and hover flies warm up by basking in the sun?
often in the middle of a flower, such as the arctic dryad
or arctic poppy.

Certain butterflies, such as Polaris fritillary, spread
their wings and point them at the sun like solar panels

: land
5 from

; by

> grow

Brown ( grizzly ) bear. Thick
fur insulates this bear from
the cold and affords it some
protection from insects in the
summer. Hibernation and a
willingness to eat just about
anything help the grizzly to
sun’ive the arctic climate.

Marsh marigold, nose bot
fly, and mosquito larvae. The
marsh marigold's bowl¬
shaped flowers follow the sun
and focus light in toward the
pollen and seed portion of the
plant. Like all insects, the
nose bot fly is cold-blooded
and often warms up by bask¬
ing in flowers. Mosquitoes
take advantage of the tun¬
dra ’s large areas of standing
water to deposit their eggs.
Once the larvae emerge, they
immediately begin feeding on
bacteria, microscopic plants,
and pollen.

to collect heat.

Bumblebees shiver their flight muscles
to generate heat and trap the warmth in
their velvety fur. While there are more
than 20,000 species of bees worldwide,
only two have adapted to life in the
Arctic, and both shiver. Amazingly,
these bees can increase their body tem¬
perature as much as 15°C above the air
temperature! That means that even when
it’s freezing outside and most insects can
hardly move, the bees are flying out to
find nectar and pollen for their colony.

Probably the most cold-hardy of all
insects is the arctic woolly bear, a cater¬
pillar that spends most of its 14-year
life frozen solid. Even for a thumb¬
sized creature, this is no small feat.
When body fluids freeze, they expand,
form ice crystals, and damage cells and
living tissues, most often killing the
organism. The woolly bear combats the
effects of freezing by producing special
chemicals. During the fiercely cold arc¬
tic winters, these chemicals prevent ice
from forming inside the cells of the
caterpillar, even when ice does form in
the space between cells, in the gut, and
in the blood. This adaptation allows the
woolly bear to withstand temperatures
as low as -70°C.

Investigation: Size and Heat

Background: Biologists have noticed that many tundra birds and
mammals are larger and have smaller appendages than do similar
species living in warmer environments. Tundra hares, for example, are
among the largest hares and have shorter ears and legs than do desert
hares (called jackrabbits). Similarly, arctic foxes have shorter ears than
do desert kit foxes. Even lemmings are larger and have smaller ears
and tails than do most other mouse-like animals. Large size and short
appendages are adaptations that reduce heat loss and resist the cold.

The amount of heat loss increases as the proportion of exposed
surface area to body mass increases. Since that proportion is greater in
small animals, they lose heat more quickly. An animal with long legs,
ears, or a tail has more surface area than an animal of the same size
that has shorter appendages.

However, in some cases, small size can be an adaptation for sur¬
vival on the tundra. Why? A small organism can survive on less food
than can a large organism of the same species. Shrews, the smallest of
all mammals, thrive in the tundra of arctic Alaska.

Materials, Part 1: Each work station should have two laboratory-
type thermometers; large and small containers made of the same
material (two tin cans or two plastic jugs, for example); hot tap water;
access to cold temperatures outdoors or to a refrigerator; the
Adaptation Cards (pictured below); and a posted set of instructions.

Materials, Part 2: Each work station should have one pair of latex
gloves; several rubber bands; two laboratory-type thermometers; warm
water; graduated cylinders or beakers; two containers of at least 250 mL
capacity; access to cold temperatures outdoors or to a refrigerator; the
Adaptation Cards (pictured below); goggles; and a posted set of instructions.

Instructions: Part 1

Which will lose heat and grow cold faster, a large object or
a small object? Test your hypothesis with the following
investigation.

1. Fill the large and small containers with hot water. Measure
and record the water temperature in each container.

2. Place both containers outside or in a cold place for 15
minutes. Again, measure and record the water temperature in
each container.

3. Find the difference between the starting and ending
readings for both containers. Which container’s contents
cooled down more? Did your prediction match your
results?

4. Based on what you found out about the relationship
between cooling and the size of the objects, do you think
animals living in tundra environments would be larger or
smaller than animals living in warm environments?

5. Using the Adaptation Cards, compare the sizes of the ani¬
mals in each pair. Which animals are larger — the ones living
on the tundra or the ones living in a warm environment?
Which moose do you think would be larger, one native to
Wyoming, or one native to Alaska? Try to find out if you
are correct.

Instructions: Part 2

Which one do you think keeps your hands warmer, mittens or
gloves? Test your hypothesis with the following investigation.

1. While wearing goggles, close off each of the five finger
compartments in one of the gloves. Be sure the rubber bands
are tight. This will be called the “mitten.” The other glove
will be called the “normal glove.”

2. Measure and record the temperature of the warm water.

3. Pour 250 mL of the water into the “mitten.” Tightly close
the top of the “mitten" glove with another rubber band.

4. Pour 250 mL of the water into the “normal glove,” so that
water runs into the finger compartments. Close the top of
this glove with another rubber band. Again, be sure to close
it tightly so it won't leak.

5. Place both gloves in a cold place (a refrigerator, or out¬
doors if the temperature is cold enough), near each other, but
not touching. Wait 15 minutes. Pour the water from the “mit¬
ten” into one container and the water in the “normal glove”
into another container. Measure and record the temperature
of the water in both containers.

6. In which glove did the water temperature decrease? How
would you explain this difference? Next time it’s cold and
you go outside, will you wear mittens or gloves to keep your
hands warm?

7. Now, think about animals living on the tundra. The blood
in their bodies is like water in the gloves. Their toes, ears,
and tails are like the fingers in the glove. Considering what
you learned from this exercise, which animal do you think
would stay warmer in the tundra, one with long ears, toes,
and tail, or one with short ears, toes, and tail?

8. Looking at the Adaptation Cards, compare the appen¬
dages (ears, tails, legs, and so on) of the arctic animals to
those of the warm-climate animals. Give a reason for the
differences you observe.

Teacher Wrap-up

In the first part of this investigation, students observe that the
small container lost heat more quickly than did the large container.
Heat loss increases as the proportion of exposed surface area to body
mass increases. Since that proportion is greater for the small container
than for the large one, the small container loses heat more quickly. In
the second part of the investigation, students observe that heat loss is
greater for the glove than for the mitten. This is because the glove has
a greater surface area than does the mitten.

The Adaptation Cards can help students make the connection
between their investigations and animal adaptations. Tundra birds and
mammals are larger and have smaller appendages than do similar
species in warmer environments and, therefore, retain heat better than
do their desert counterparts.

These activities were adapted with permission from Alaska's Tundra and
Wildlife: Alaska Wildlife Curriculum Teacher's Guide, published in 1995 by
the Alaska Department of Fish and Game.

Arctic fox. Thick fir provides
warmth for this arctic resident,
changing color from summer
(red-brown) to winter (white).
Compared to foxes that live in
warmer climates, the arctic fox
has smaller ears, minimizing
loss of body heat.

Finding Food

The menu of available food in the
Arctic changes with the seasons. The
summer is like an all-you-can-eat buf¬
fet. The sun shines 24 hours a day,
snow melts, and plants soak up the sun
and grow rapidly. Tundra ponds thaw
and become thick with water plants,
insect larvae, and shellfish. Millions of
ducks, geese, loons, gulls, sandpipers,
and other migrating birds return, ready
to nest, have young, and gorge them¬
selves. Great herds of caribou also
arrive from their winter homes to give

birth and feast on plants. Wolves, bears, and other predators also take part
in the foodfest. And let’s not forget the mosquitoes, sucking blood from
any animal, large or small.

The winter menu, on the other hand, is bleak. There is little sunlight,
plants are snow-covered, and the summertime crowds have left. The hardy,
year-round residents are left to for; ge for what little food remains.
Microscopic organisms, plants, and insects go into a state of dormancy —
they stop growing, moving, and/or breathing — so they don’t need food.

Because birds and mammals breathe, they can’t go
completely dormant; instead, animals like the grizzly
bear and arctic ground squirrel hibernate.

Hibernating animals become inactive, their breathing
and heart rates slow, and they have little need for
food energy beyond that supplied by stored fat.

Another food-related adaptation is moving or
migrating for food. This is the strategy of millions of
birds that arrive in the summer when food is plenti¬
ful and leav^ in the winter, when food runs out. The
arctic tern, considered to be the world’s greatest
traveler, flies from the Antarctic Ocean near the
South Pole all the way to the Arctic to spend the
summer breeding and nesting.

Caribou also migrate. Living on the tundra dur¬
ing the summer, they feed mostly on grasses, sedges,
birch, and willow. In the winter, many caribou
migrate to the moist northern forests where they feed
on lichen, a plant composed of fungus and algae.

hits the leaves, they begin to makerfood for > f,J

the plant right away, thus providing a clear * s

advantage over plants that must wait for new t

leaves to break out and unfurl. >

XX-i-:

Ground squirrel. Thick fur
protects this squirrel from the
cold during hibernation.

Prior to hibernation, the
squirrel stores food to be
eaten in the spring before
new plant growth appears.

Producing and Protecting
Young in the Arctic

Of course, there is more to life on the tundra
than just keeping warm. Finding food, and
avoiding predators. Animals have to raise
their young, too, and do so quickly, before
the short summer ends.

Birds that migrate to the Arctic have to
find mates, build nests, lay eggs, hatch them,
and feed their young to the point where they
can fly — all in 10-14 weeks! So why do mil¬
lions of birds fly from all over the world to
the Arctic? First, food is plentiful, especially
high-energy foods like insects that young
birds need. There are also fewer predators

:tJA

Kit fox. A creature of warmer
latitudes and less seasonal
change, this fox's fur does not
change color with the seasons.
And, unlike the arctic fox, the
kit fox’s ears are rather large.
For this animal, heal retention
isn 7 desirable, and the more
of it lost by radiating out from
those ears, the better.

Snowshoe hare. This arctic
animal congregates in large
groups, which helps to create
confusion when the hares scat¬
ter before the onslaught of
predators. The hare 's large,
padded feet act as snowshoes,
and its coat changes color
from winter (white) to summer
(brown) to camouflage it from
predators. Small ears help to
reduce loss of body heat.

than in the south. And parents have more “working hours,” provided by the
constant sunlight, in which to feed their young.

No matter what the climate, it
takes a lot of energy to have
young, feed them, and raise them.
Because food can be scarce even
in the arctic summer, most ani¬
mals have adapted the ability to
adjust the number of young they
produce, depending on environ¬
mental conditions. For example, if
the snow remains in the spring
longer than usual, food sources
remain covered. Some migratory
birds, such as geese and swans,
respond by laying fewer eggs or none
at all. Meat-eating animals like arctic
foxes, weasels, and snowy owls will
produce fewer young when their main
food source — lemmings — is scarce.

Caribou and musk oxen put on a lot
of fat in the late summer, but not just to
prepare for winter food shortages. These
animals also need large amounts of food
energy for the mating season and birth
process. Males need energy for doing
battle with antlers or horns in an effort to win mating rights. Pregnant
females need energy to sustain developing fetuses over the winter, and to
care for the calves bom in the spring.

Even mosquitoes need energy to have young. To get that energy,
female mosquitoes drink blood. In fact, most female mosquitoes found
worldwide must have a blood meal before they ran lay eggs. Arctic
species, however, can lay at least a few eggs even if they can’t get blood,
because they build up enough food reserves for this purpose as larvae. Of
course, these mosquitoes can lay many more eggs after a quick slurp from
some unsuspecting animal. And slurp they do, by the billions. In just one
week’s time, a single caribou can lose two liters of blood to mosquitoes.

The insects don’t get off scott free, however; yellow jackets catch mosqui¬
toes on the wing and feed them to their grubs.

With the summer so short, most plants on the arctic tundra do not have
enough lime to make seeds. Instead, the plants spread vegetatively, without
producing seeds. For example, some plants grow runners above ground or
below ground that reach out and form new, separate plants. Others grow
little buds that fall off, blow away in the wind, and start to take root once

they land in a good growing spot.

Those plants that do produce
seeds rely heavily on mosquitoes
and other insects of the far north to
facilitate pollination. Some plants,
like the Pallas’s wallflower and
prickly saxifrage, use the high arc¬
tic winds to their advantage. At the
beginning of summer, for example,
the plant stalks are short. Once the
seeds are ready, the stalks grow tall,
pushing the seed pods up above the
fall snow cover. The high winds
blow the seeds over the slippery,
crusty snow, sending them over a
wide area.

Life in the Arctic goes on,
despite the brutally tough condi¬
tions. Faced with bone-chilling
temperatures, relentless winds, and
dramatic changes in the seasons,
life does one thing: It adapts.

Jackrabbit. This warm-
climate creature stays the
same color year-round
because there is not much
seasonal variation in its envi¬
ronment. Note the large ears;
the more heat lost through
radiation from the ears, the
better.

/jrtttSy

This squirrel, typically
20 to 32 centimeters long
and weighing one kilogram,
has thick fur. It can hiber¬
nate for several months,
living off stored fat.

This warm-climate squirrel,
typically 15 centimeters long
and weighing 90 grams, has
short fur and a fairly long
tail. It must eat year-round
but can survive for weeks
without water.

n r- riV-A

. M ■*!

l A % v., .. (

/ x • :\e

dwtfoFox

This fox, usually
weighing 3-6 kilograms, has
long, warm fur
that turns white in
winter and short ears.

X •<

&J2

ffit fox

This desert fox, usually
weighing 1-3 kilograms,
is light brown year-round
and has large ears.

fSk

aim

tJsUxfn / f

Mart

This mammal has long,
dense fur that turns
white in winter and
fairly short ears.

This mammal has short
fur that stays light
brown year-round and very
large ears.

Jgfr.

: #

rfPv

This arctic mammal has
thick fur that turns white
in winter and a short tail,
small ears, and short legs.

ffmyaroo Rat

This desert mammal has
short fur that stays light
tan year-round and a
long tail, long ears,
and long legs.

, — jt ..T£r~

This large, white bird
feeds on small mammals.
It nests on the ground.

Grmt

This large, brown bird
feeds on small mammals.
It builds stick nests in trees.

(I S KfJUtTMENT Of THE in TEAM ^

N’iBwsAtg -. -f-1

gmdfrfo? tfogQrvtfa Jtmfrtt:
/f £ook at CoM-h/wtMr

By Jeff B rune

/fTkeep warm on a cold day, you might pile on extra clothing or have a
cup of hot chocolate. The nose bot fly of the frigid Arctic takes a decided¬
ly different approach to staying warm. It takes refuge in the warm, steamy
nose of a caribou. Once in the nostril, the fly withstands the snorts of the irri¬
tated animal and quickly deposits its wormy offspring. The maggots then
crawl through the caribou’s nose passages and settle in its throat, where they

spend the winter warmed by the caribou’s
body heat and feed off its tissues. When spring
arrives, the well-fed maggots are coughed up
or sneezed to the ground, where they turn into
adult flies and begin the cycle again.

plentiful food, endless hours shreds. When the growing season lasts only

of daylight in which to eat, 10-14 weeks and the soil has few nutrients, it’s

he front of this foldout depicts the Alaskan tundra in late spring. As the snow melts, the
region’s flora and fauna become more visible and active. Purple monkshood, bog rose¬
mary (red), and tundra rose (yellow) grow and flower, as do many varieties of moss and
lichen (lower right). Often, plants in the nutrient-poor soil benefit from the spot fertilization of ani¬
mal droppings or the decayed remains of dead animals and plants. Tussocks of sedges and grass¬
es, which tend to grow in clumps (cen ter right), provide food and shelter for wildlife but create a
tricky surface for people to traverse on foot.

was eroded by the stream. Ice also is responsible for another prominent feature of the tundra, the

sir

A . ■

When fur or feathers are not

enough to stay warm, arctic animals seek shelter. For example, to
escape the cold winter winds, the ptarmigan takes flight and
dives into a drift of soft snow. The snow blankets the land
and acts as a good insulator, trapping heat that comes from
the ground. Diving from the air, the ptarmigan leaves no
tracks for predators to follow.

Plants shelter themselves from the arctic elements by
growing low to the ground. In the arctic summer, the dark-
colored ground absorbs energy from the sun, so plants grow
close to the warm ground rather than towering above it.

In the winter, snow blankets and protects arctic
plants from the wind and cold. Any twigs that do
extend above the snow are slowly ground down by
the sharp ice and snow blowing along the surface.

Insects battle the cold in many intriguing ways.

T ' tv VVv

K;f~" m
A"

V ■ \A\ s'A

l.sf " 4 4
A* •< ■ A

Brown ( grizzly ) bear. Thick
fur insulates this bear from
the cold and affords it some
protection from insects in the

Investigation: Size and Heat

pingo ( the hill on the far edge of the polygonal ground with red soils exposed). Essentially an ice-
filled blister, a pingo can attain a height of more than 30 meters. Eventually the summit can rup¬
ture and thaw, creating a water-filled crater lake or collapsing the structure altogether.

The tundra’s human population is sparse. Permanent settlements are few and far between,
most being Inuit villages along the coast. Seasonal populations include scientists and naturalists.
Transportation is difficult and often accomplished by light aircraft and helicopters. But, as indicat¬
ed by the ancient arrowhead pictured, our ancestors traveled the area on foot, as long as 10-12
thousand years ago, hunting and making a life for themselves.

r Science

&CHILDREN

Instructions: Part 2

Which one do you think keeps your hands warmer, mittens or
gloves? Test your hypothesis with the following investigation.

2. Measure and record the temperature of the warm water.

3. Pour 250 mL of the water into the “mitten.” Tightly close
the top of the “mitten” glove with another rubber band.

6. In which glove did the water temperature decrease? How

f \

•4 L. v

■ ii

' 5 *•»..

Arctic fox. Thick fur provides
warmth for this arctic resident,
changing color from summer
(red-brown) to winter (white).
Compared to foxes that live in
wanner climates, the arctic fox
has smaller ears, minimizing
loss of body heat.

Finding Food i f t %

birth and feast on plants. Wolves, bears, and other predators also take part
in the foodfest. And let's not forget the mosquitoes, sucking blood from
any animal, large or small.

The winter menu, on the othei hand, is bleak. There is little sunlight,
plants are snow-covered, and the summertime crowds have left. The hardy,
year-round residents are left to for ge for what little food remains.
Microscopic organisms, plants, and insects go into a state of dormancy —
they stop growing, moving, and/or breathing — so they don’t need food.

Because birds and mammals breathe, they can’t go
completely dormant; instead, animals like the grizzly
bear and arctic ground squirrel hibernate.

Hibernating animals become inactive, their breathing
and heart rates slow, and they have little need for
food energy beyond that supplied by stored fat.

Another food-related adaptation is moving or
migrating for food. This is the strategy of millions of
birds that arrive in the summer when food is plenti-

than in the south. And parents have more “working hours,” provided by the
constant sunlight, in which to feed their young.

Even mosquitoes need energy to have young. To get that energy,
female mosquitoes drink blood. In fact, most female mosquitoes found

Kit fox. A creature of warmer
latitudes and less seasonal
change, this fox’s fitr does not
change color with the seasons.
And, unlike the arctic fox, the
kit fox’s ears are rather large.
For this animal, heat retention
isn ’t desirable, and the more
of it lost by radiating out from
those ears, the better.

and a comparative lack of not easy for plants to make food. Similarly,

predators, snow geese and when the sun sets for more than two months and

many other migrating birds the only light to hunt by comes from the moon

flock to the tundra during the or the eerie shimmer of the northern lights, ani-
summer months. mals have a hard time finding sustenance.

Keeping Warm

Life-forms on the tundra have devised
numerous ways of dealing with the
arctic chill.

r r**

■

Arctic tern. These birds create
their own “endless summer”
by commuting between the
Arctic and Antarctic, visiting
each during periods of con¬
stant daylight.

tundra through the winter months.

The hardy residents that stay in the
Arctic year-round have developed spe¬
cial adaptations to brave the chill.

often in the middle of a flower, such as the arctic dryad
or arctic poppy.

Certain butterflies, such as Polaris fritillary, spread
their wings and point them at the sun like solar panels

to collect heat.

summer. Hibernation ana a
willingness to eat just about
anything help the grizzly to
survive the arctic climate.

Marsh marigold , nose bot
fly, and mosquito larvae. The

marsh marigold’s bowl¬
shaped flowers follow the sun
and focus light in toward the
pollen and seed portion of the
plant. Like all insects, the
nose bot fly is cold-blooded
and often warms up by bask¬
ing in flowers. Mosquitoes
take advantage of the tun¬
dra ’s large areas of standing
water to deposit their eggs.
Once the larvae emerge, they
immediately begin feeding on
bacteria, microscopic plants,
and pollen.

Bumblebees shiver their flight muscles
to generate heat and trap the warmth in
their velvety fur. While there are more
than 20,000 species of bees worldwide,
only two have adapted to life in the
Arctic, and both shiver. Amazingly,
thes ' bees can increase their body tem¬
perature as much as 1 5°C above the air
temperature! That means that even when
it’s Ireezing outside and most insects can
hardly move, the bees are flying out to
find nectar and pollen for their colony.

Instructions: Part 1

Which will lose heat and grow cold faster, a large object or
a small object? Test your hypothesis with the following
investigation.

1. Fill the large and small containers with hot water. Measure
and record the water temperature in each container.

2. Place both containers outside or in a cold place for 15
minutes. Again, measure and record the water temperature in
each container.

3. Find the difference between the starting and ending
readings for both containers. Which container’s contents
cooled down more? Did your prediction match your
results?

/jrctttr

Grote/td fjfjurref

This squirrel, typically
20 to 32 centimeters long
and weighing one kilogram,
has thick fur. It can hiber¬
nate for several months,
living off stored fat.

s?S35

faff’,!)/'

/.‘i

Sfitirref

This warm-climate squirrel,
typically 15 centimeters long
and weighing 90 grams, has
short fur and a fairly long
tail. It must eat year-round
but can survive for weeks
without water.

/V T -v~ ^

M w A ./ ;/ 4, \

/ n.

< l\

S'?) <S ;,i - /

! '■ }

* V ■’ J

m ,
% \
V \

FrotiC' Fox

This fox, usually
weighing 3-6 kilograms, has
long, warm fur
that turns white in
winter and short ears.

irv^i

Fit Fox

This desert fox, usually
weighing 1-3 kilograms,
is light brown year-round
and has large ears.

tytoh/sfm f/zirtz

This mammal has long,
dense fur that turns
white in winter and
fairly short ears.

you go outside, will you wear mittens or gloves to keep your
hands warm?

7. Now, think about animals living on the tundra. The blood
in their bodies is like water in the gloves. Their toes, ears,
and tails are like the lingers in the glove. Considering what
you learned from this exercise, which animal do you think
would stay warmer in the tundra, one with long ears, toes,
and tail, or one with short ears, toes, and tail?

8. Looking at the Adaptation Cards, compare the appen¬
dages (ears, tails, legs, and so on) of the arctic animals to
those of the warm-climate animals. Give a reason for the
differences you observe.

Teacher Wrap-up

These activities were adapted with permission from Alaska's Tundra and
Wildlife: Alaska Wildlife Curriculum Teacher’s Guide , published in 1995 by
the Alaska Department of Fish and Game.

arctic tern, considered to be the world’s greatest
traveler, flies from the Antarctic Ocean near the
South Pole all the way to the Arctic to spend the
summer breeding and nesting.

Plants, too, have adapted to the Arctic. They
make food faster and at lower temperatures than do
plants in warmer climates. The alpine saxifrage, for
example, has leaves that survive the winter
without shriveling up. Once the spring sun
hits the leaves, they begin to make food for
the plant right away, thus providing a clear
advantage over plants that must wait for new

leaves to break out and unfurl. if" \ >

Ground squirrel. Thick fur
protects this squirrel from the
cold during hibernation.

Prior to hibernation, the
squirrel stores food to be
eaten in the spring before
new plant growth appears.

Producing and Protecting
Young in the Arctic

Of course, there is more to life on the tundra
than just keeping warm, finding food, and
avoiding predators. Animals have to raise
their young, too, and do so quickly, before
the short summer ends.

Snowshoe hare. This arctic
animal congregates in large
groups, which helps to create
confusion when the hares scat¬
ter before the onslaught of
predators. The hare ’s large,
padded feet act as snowshoes,
and its coat changes color
from winter (white) to summer
(brown) to camouflage it from
predators. Small ears help to
reduce loss of body heat.

species, however, can lay at least a few eggs even if they can’t get blood,
because they build up enough food reserves for this purpose as larvae. Of
course, these mosquitoes can lay many more eggs after a quick slurp from
some unsuspecting animal. And slurp they do, by the billions. In just one
week’s time, a single caribou can lose two liters of blood to mosquitoes.
The insects don’t get off scott free, however; yellow jackets catch mosqui¬
toes on the wing and feed them to their grubs.

With the summer so short, most plants on the arctic tundra do not have
enough time to make seeds. Instead, the plants spread vegetatively, without
producing seeds. For example, some plants grow runners above ground or
below ground that reach out and form new, separate plants. Others grow
little buds that fall off, blow away in the wind, and start to take root once

they land in a good growing spot.

crusty snow, sending them over a
wide area.

Life in the Arctic goes on,
despite the brutally tough condi¬
tions. Faced with bone-chilling
temperatures, relentless winds, and
dramatic changes in the seasons,
life does one thing: It adapts.

Tfesert

This mammal has short
fur that stays light
brown year-round and very
large ears.

This arctic mammal has
thick fur that turns white
in winter and a short tail,
small ears, and short legs.

This desert mammal has
short fur that stays light
tan year-round and a
long tail, long ears,
and long legs.

11 W

3mm/

This large, white bird
feeds on small mammals.
It nests on the ground.

Grmt t tyor/wt
Od/f

This large, brown bird
feeds on small mammals.
It builds stick nests in trees.

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